Related papers: Large-Scale Outer Rings of Early-type Disk Galaxie…
Star formation in starbursts appears to be biased toward compact clusters, with up to 20% of all stars formed in them. Observations with HST show that many of these clusters have luminosities (-9 > Mv > -16), UBVI colors, and half-light…
The stellar content of the nearby SB(s)m galaxy NGC 55 is investigated using images covering the visible and near-infrared wavelength regions. A well-defined plume, which stellar evolution models suggest contains stars with masses near the…
Since giant planets scatter planetesimals within a few tidal radii of their orbits, the locations of existing planetesimal belts indicate regions where giant planet formation failed in bygone protostellar disks. Infrared observations of…
We study star formation rates (SFR) and stellar masses in bulges of nearby disk galaxies, using SFRs and stellar masses derived from Spitzer and GALEX data. At present day SFR the median pseudobulge could have grown the present day stellar…
Photometry and long-slit spectroscopy are presented for 14 S0 and spiral galaxies of the Fornax, Eridanus and Pegasus cluster, and NGC 7582 group. The structural parameters of the galaxies are derived from the R-band images by performing a…
Stars in disks of spiral galaxies are usually assumed to remain roughly at their birth radii. This assumption is built into decades of modelling of the evolution of stellar populations in our own Galaxy and in external systems. We present…
We study the protoplanetary disk lifetimes using a large sample of young stellar objects in nearby clusters. To investigate the final phase of disk dissipation, we selected 32 clusters, located within 500 pc and aged between 1 and 100 Myr,…
Recent observations have suggested that circumstellar disks may commonly form around young stellar objects. Although the formation of circumstellar disks can be a natural result of the conservation of angular momentum in the parent cloud,…
The high rate of planet detection among solar-type stars argues that planet formation is common. It is also generally assumed that planets form in protoplanetary discs like those observed in nearby star forming regions. On what timescale…
We present IRAC/MIPS Spitzer observations of intermediate-mass stars in the 5 Myr old Lambda Orionis cluster. In a representative sample of stars earlier than F5 (29 stars), we find a population of 9 stars with a varying degree of moderate…
We consider models of gas flow in spiral galaxies in which the spiral structure has been excited by various possible mechanisms: a global steady density wave, self-gravity of the stellar disc and an external tidal interaction, as well as…
The study of the Milky Way stellar discs in the context of galaxy formation is discussed. In particular we explore the properties of the Milky Way disc using a new sample of about 550 dwarf stars for which we have recently obtained…
The stellar disks of many spiral galaxies are twice as large as generally thought. We use archival data from the Galaxy Evolution Explorer mission (GALEX) to quantify the statistical properties of young stellar clusters in the outer,…
This is the second paper of a series devoted to study the stellar content of early-type galaxies. The goal of the series is to set constraints on the evolutionary status of these objects. We use a new set of models which include an improved…
Quantification of the Galaxy's star formation history involves both the duration and the rate of formation, with these parameters being known with different precision for different populations. The early rate of star formation is knowable…
We perform a "fossil record" analysis for ~800 low-redshift spiral galaxies, using STARLIGHT applied to integral field spectroscopic observations from the SDSS-IV MaNGA survey to obtain fully spatially-resolved high-resolution star…
The present paper presents a tabulation of data on all 600 Galactic open clusters for which it is presently possible to calculate linear diameters. As expected, the youngest `clusters' with ages < 15 Myr, contain a significant (greater than…
Deep near-infrared images recorded with NICI on Gemini South are used to investigate the evolved stellar content in the outer regions of the south east quadrant of the spiral galaxy M83. A diffuse population of asymptotic giant branch (AGB)…
Stellar photometry of nearby irregular galaxies of the Local Group is used to identify and study the young and old stellar populations of these galaxies. An analysis of the spatial distributions of stars of different ages in face-on…
The normalized radial distribution of young stellar populations (and cold gas) in nearby galactic disks is compared between AGN host galaxies and starforming galaxies (both with Hubble types between S0/a and Scd) by using type II supernovae…